JPH0228850B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Field of Application] The present invention relates to a contact lens cleaning composition containing solid particles. [Prior art] Since contact lenses are worn directly on the eyes,
Eye secretions such as proteins and lipids adhere to the lens surface, and if this dirt is not removed, not only will the wettability of the lens surface and the optical properties of the lens be impaired, but it will also cause damage to the eyeballs. However, it may cause damage. Therefore, contact lenses must be thoroughly cleaned before use. Conventional hard contact lenses made of polymethyl methacrylate are chemically stable, so they can be used with a wide variety of cleaning agents and are easy to rinse, so there are relatively few problems with dirt adhesion. Dirt that is difficult to remove may accumulate. In recent years, lenses with high oxygen permeability have been developed to improve wearability, but generally the surface of these lenses has the property of strongly adhering dirt, making it physically difficult to remove dirt. Since various materials are used in these types of lenses, there are many restrictions on the types of cleaning agents that can be used due to their chemical stability, and a highly versatile cleaning agent that is suitable for these types of lenses is particularly desired. There is. Conventionally, surfactants or proteolytic enzymes have been used as cleaning agents for contact lenses, but depending on the lens material, surfactants alone may not have sufficient cleaning effect, and proteolytic enzymes may be used for cleaning other than proteins. It also has the disadvantage that it has a low removal effect on dirt and requires time to work. Therefore, contact lens cleaning compositions containing abrasives have been proposed in order to physically remove dirt (Japanese Patent Application Laid-open Nos. 56-6215 and 1982-192922). [Problems to be Solved by the Invention] Conventional contact lens cleaning compositions containing an abrasive are made by dispersing a solid abrasive in a cleaning liquid containing a surfactant. If the abrasive is not evenly dispersed in the cleaning solution, it will not only lower the product value, but also cause a difference between the composition at the beginning of use and the composition at the end of use. becomes high and can cause scratches on the lens. Therefore, a dispersant is always used in conventional cleaning compositions containing an abrasive for the purpose of uniformly dispersing the abrasive. Dispersants include celluloses such as hydroxyethylcellulose and carboxymethylcellulose, clays such as bentonite and montmorillonite, a combination of salt and anionic surfactant,
Water-soluble polymers such as poly-N-vinylpyrrolidone and polyvinyl alcohol are known, but cellulose-based dispersants have the disadvantage of being sticky and difficult to rinse, and clays are natural products. Therefore, the particle size is uneven and easily scratches. In addition, the combination of salt and anionic surfactants and water-soluble polymers may change their effects due to changes in conditions such as pH and temperature, so any effects other than those as a dispersant are preferable. It wasn't something. The present invention provides a contact lens cleaning composition that contains solid particles and has an excellent cleaning effect. In particular, the solid particles can be uniformly dispersed without using a conventionally used dispersant, and stable cleaning can be achieved. The object is to provide a cleaning composition of this kind that can be effective. [Means for solving the problem] As a result of extensive research in order to achieve the above objective, it was found that by limiting the particle size and distribution of the solid particles to be contained within a predetermined range, it was possible to achieve uniform dispersion without using conventional dispersants. It has been discovered that stable solid particle-containing cleaning compositions can be formed. That is, the contact lens cleaning composition of the present invention has a cleaning composition that contains 100 parts of a cleaning solution containing a surfactant.
1 part to 20 parts of solid particles with an average particle size of less than 1 micron
part, and contains 0.1 part to 20 parts of solid particles having an average particle size of 1 micron to 10 microns. The present invention will be explained in detail below. The solid particles used in the present invention may be either inorganic or organic, and examples of inorganic particles include:
For example, silica, alumina, calcium carbonate, etc. can be used, and as the organic material, various organic polymers can be used. Among these, silica and alumina are preferred, and silica is particularly preferred. In the present invention, for 100 parts of cleaning liquid,
1 part to 20 parts (preferably 1 part to 5 parts) of solid particles with an average particle size of less than 1 micron, an average particle size of 1 micron to
0.1 part to 20 parts (preferably 1 part to 10 parts) of 10 micron solid particles are included. If the amount of solid particles having an average particle size of less than 1 micron is less than the above range, the dispersion effect of the solid particles as a whole will be small, and if it is more than the above range, the entire cleaning composition will approach a solid state, which is not preferable. On the other hand, if the solid particles having an average particle size of 1 to 10 microns are less than the above range, the polishing and cleaning effect of the contact lens will not be sufficient, and if it is larger than the above range, the lenses will be easily scratched, which is not preferable. The solid particles classified into two types according to their average particle diameters may be of the same type or may be of different types. Solid particles with an average particle size of 1 micron to 10 microns are preferably prepared by combining solid particles with different average particle sizes within this range, and the solid particles including solid particles with an average particle size of less than 1 micron are preferably prepared by combining solid particles with different average particle sizes within this range. It is desirable to make the diameter distribution as continuous as possible. The cleaning liquid containing solid particles usually contains 1 to 50% by weight of a surfactant, and the surfactant may include various surfactants such as nonionic surfactants, cationic surfactants, and anionic surfactants. Although these surfactants can be used alone or in combination, it is preferable to use nonionic surfactants because they have less effect on the eyes. [Function] There are few contact lens cleaning compositions that contain solid particles, and this is because it was conventionally thought that solid particles would scratch the lens surface, but the solid particles used in the present invention have an average They are fine particles with a particle size of 10 microns, so they do not have enough anti-friction properties to impair the optical performance of the lens, and even if they remain on the lens after cleaning, they have very little effect on the eyes. In the present invention, solid particles with an average particle size of 1 to 10 microns act as an abrasive to enhance the physical cleaning effect, but in addition, solid particles with an average particle size of 1 to 10 microns, which have a relatively small physical cleaning effect, are used as an abrasive. When solid particles of micron size or less are added in a predetermined proportion, uniform dispersibility of the solid particles as a whole can be obtained without adding a dispersant, and therefore a contact lens cleaning composition having a stable cleaning effect can be obtained. In addition, according to the present invention, there is no need for a dispersant, which was necessary in the prior art to uniformly disperse the abrasive, but it goes without saying that a dispersant may be added as a supplement depending on the compounding conditions. be. Even in this case, there is an advantage that only a small amount of dispersant is required. [Example] Examples of the present invention are shown below, but the present invention is not limited to these Examples. Dispersion Stability of Cleaning Composition Cleaning compositions were prepared with the compositions shown in Table 1, and the dispersion stability of solid particles after being left at room temperature for 3 months was tested. As fine silica powder, "Aerosil" (trade name) manufactured by Nippon Aerosil Co., Ltd. and "Rheolo Seal" (trade name) manufactured by Tokuyama Soda Co., Ltd. were used. Examples 1 and 2 are cases in which the average particle size distribution of solid particles is made as continuous as possible. As shown in Table 1, both showed good stability without sedimentation of solid particles even after being left at room temperature for 3 months. In Example 3, the continuity of the average particle size distribution of the solid particles was inferior to that in Examples 1 and 2, and slight separation was observed in the upper layer after being left at room temperature for 3 months, but it became uniform when shaken. It became a state. On the other hand, when solid particles with an average particle size of less than 1 micron were not added (Comparative Example 1), precipitation of solid particles was observed within one week, and cellulose instead of solid particles with an average particle size of less than 1 micron was observed. When a thickener of the same type was blended (Comparative Example 2), it felt quite sticky, had poor cleaning and rinsing properties, and flaky solid particles were observed to settle within two weeks.

[Table] ○…Good
×...Characteristics when using poor cleaning composition The cleaning composition of Example 1 in Table 1 was used to evaluate the characteristics when using the product of the present invention. This cleaning composition dissolves a nonionic surfactant in purified water,
Add a predetermined amount of solid particles and heat at a temperature of about 80℃ for 15-20
Prepared by stirring at high speed for 1 minute. Target lens is relatively hard (Bitzkers hardness 15)
Using an oxygen-permeable siloxanyl methacrylate hard contact lens (A) and a relatively soft (Vickers hardness 12) contact lens of the same type (B),
The following items 1 to 3 were evaluated. The results are shown in Table 2. 1. Ease of scratching Hand washing (procedure): Apply 2 to 3 drops of the cleaning composition to the lens, wash with your hands for 1 minute, and then rinse with running water. This cycle is repeated 120 times, and the degree of scratches on the lens surface before and after cleaning is observed using a Nikon stereoscopic optical microscope (eyepiece x 15, objective x 10). (Evaluation): - No scratches + Some scratches Cleaning (Procedure): Apply 2 to 3 drops of the cleaning composition to a polishing cloth and clean the lens with this polishing cloth for 3 minutes. Observe the degree of scratches on the lens surface before and after cleaning using a Nikon stereoscopic optical microscope (eyepiece x 15, objective x 10). (Evaluation): - No scratches + Scratches 2 Polishability Hand washing (Procedure): Carve the shipping name on the front of the lens. Apply 2 to 3 drops of the cleaning composition, wash your hands for 1 minute, and then rinse with running water. Repeat this cycle 120 times and observe the degree of reduction in the markings before and after cleaning using a Nikon stereo optical microscope (eyepiece x 15,
Observe with a 10x objective. (Evaluation): - No change +... The markings become fainter Machine polishing (Procedure): Apply 2 to 3 drops of the cleaning composition to the lens where the whirl remains during lens processing.
Polish for 2 minutes with a single-shaft polisher. Observe the condition of the whirlpool before and after polishing using a Nikon stereomicroscope (eyepiece x 15, objective x 10). (Evaluation): -... No change +... Rotation becomes thinner 3 Cleanability (Procedure): Siloxanyl methacrylate-based oxygen permeable hard contact lens (B)
After wearing it for about a year, you can wash it with your hands if it gets dirty and cannot be removed even with enzymes. (Evaluation): ○…3 minutes of cleaning completely removes dirt ×…3 minutes of cleaning cannot completely remove dirt

[Table] [Effects of the Invention] As explained above, the present invention adds solid particles with an average particle size of 1 micron or less in a predetermined proportion in addition to solid particles with an average particle size of 1 micron to 10 microns that act as an abrasive. Therefore, uniform dispersion of the solid particles as a whole can be obtained without adding a dispersant, and various problems caused by adding a dispersant can be solved, and a cleaning composition for contact lenses with excellent cleaning effects can be created. can be provided.

Claims (1)

[Claims] 1. 1 to 20 parts of solid particles with an average particle size of less than 1 micron, and 0.1 part of solid particles with an average particle size of 1 to 10 microns per 100 parts of a cleaning solution containing a surfactant.
1. A cleaning composition for contact lenses, characterized in that it contains 1 to 20 parts. 2. The contact lens cleaning composition according to claim 1, wherein the solid particles are silica. 3. The contact lens cleaning composition according to claim 1 or 2, wherein the surfactant is a nonionic surfactant.